James J. "Whitey" Bulger, a suspected New England organized-crime boss arrested in California this week with his companion, Catherine Greig, finally faced a judge in Boston's federal courthouse this afternoon after being on the run since the mid-1990s.

Balding, bearded and dressed in a sweater and white shirt, Bulger, now 81, remained stoic as the judge discussed the charges against him, answering, "Yes, sir," in response to questions. The hearing over Bulger's continued confinement lasted 10 minutes with the judge ruling that he should remain in custody.

There was debate at a second 10-minute hearing, at which a different judge presided, over whether Bulger should have a court-appointed lawyer. The prosecution alleged Bulger had "another stash," referring to the $800,000 in cash found hidden at his California home. The judge did not make a decision.

Bulger's hands were shackled behind his back as he entered and left the court.

Three courtrooms, including the one in which Bulger appeared, were overflowing with spectators. Outside the courthouse, a crowd numbering about 100 included a mix of the media and curious onlookers.

The FBI lured the reported one-time leader of the Winter Hill Gang out of his nondescript California apartment near the Santa Monica pier by telling him that someone might have broken into his storage locker.

Once they nabbed the man allegedly connected to at least 19 murders, they found $800,000 in cash stuffed in his apartment walls and 30 weapons stored in hollowed-out books. There was also a packed bag to make for an easy getaway.

FBI officials have yet to release details about who gave police the credible tip and won't say whether the person will receive the $2.1 million reward offered for the capture of the couple.

"I can't go into details about the source of the tip that we received other than to say it was received as a direct result of the media campaign which the FBI Boston division, in coordination with FBI headquarters, launched this past Monday and Tuesday," said Richard DesLauriers, agent in charge of the FBI's Boston office.

Law enforcement officials told ABC News that it didn't surprise them that Bulger was hiding in plain sight.

"Sometimes, it's very simple to deceive when you make yourself to be a very average looking, average couple together and you just kind of, sort of blend in with the community -- and I think they were able to do that, especially as a couple and so it was very difficult," said Carmen Ortiz, U.S. attorney for Massachusetts.

"Any claim that the FBI knew Mr. Bulger's whereabouts prior to the FBI's publicity efforts this week are completely unfounded," DesLauriers said in a written statement. "When we learned his location, he was arrested promptly."

Bulger and Greig had been living under the false names Charles and Carol Gasko, officials said, and appeared to have lived in the Santa Monica home for some time. Two property managers at the Santa Monica property told the Associated Press the fugitive pair, using the Gasko name, moved there in 1996.

One neighbor described Greig as a nice person.

"My sense is that she was a very kind and lovely person and he was a bit of a lunatic," the neighbor said. "I sensed a violent nature."

Neighbors said Bulger never left the house without a hat and sunglasses. He fed squirrels outside his apartment and went for walks on the beach twice a day, at sunrise and sunset.

Bulger chuckled in a California court Thursday as he appeared in public for the first time in 16 years.

"There's a lot of media here to see you," a marshal told Bulger, according to a federal official there. The shackled Bulger just laughed.

When the judge asked Bulger during the short hearing if he had read and understood the charges listed against him in a 200-plus page indictment, Bulger said he hadn't read it all but knew what was inside.

Bulger could face life in prison for the charges against him in Boston and possibly the death penalty for charges filed elsewhere, if he is convicted, Ortiz said. Greig could face up to five years in prison for harboring a fugitive.

"I am very emotional about all this but I have to say I am happy my sister is going to coming home," she said Thursday. "I talked to her the first couple of years but I haven't talked to her since. It's been a very long time. ... I didn't know if she was alive or dead, and suddenly it is within my grasp."